In what are called continuous droplet ejection apparatus, continuous pressure is applied to liquid with a pump to push the liquid out from a nozzle, and vibration is additionally applied by vibrating manner, thereby forming a state wherein liquid is evenly ejected from a nozzle as droplets. Since droplets are continuously ejected from a nozzle with this method, it is necessary to sort droplets that are used for printing from the droplets that are not used in accordance with print data. With what is called a charge deflection method, such sorting is conducted by selectively charging droplets, deflecting the droplets with an electric field, and causing the charged droplets to fly in a trajectory different from that of the non-charged droplets. Sorted non-print droplets are captured by a gutter and collected. In order to realize these functions, a charging electrode, a deflecting electrode, and a gutter are provided along the droplet flight trajectory from a nozzle.
Patent Literature 1 discloses a method of sorting that differs from a charge deflection method and does not charge droplets. More specifically, Patent Literature 1 discloses a configuration wherein large droplets and small droplets are separately ejected by a nozzle and made to pass through a liquid curtain consisting of misted droplets that were formed along the droplet flight path. In so doing, the small droplets are captured, and only the large droplets are made to land onto a print medium. Also, Patent Literature 2, although not a continuous liquid ejection apparatus, discloses technology that causes a separate droplet to collide with a flying droplet. More specifically, Patent Literature 2 discloses a configuration wherein a droplet from a first ejection port (main droplet) is made to collide with a droplet from a second ejection port, thereby altering its flight direction. In so doing, only a satellite droplet (microdroplet) from the first ejection port is made to land onto a print medium, thereby making it possible to miniaturize print dots.